Control mechanism for crawler loader booms



Aug. 4, 1931. F. F. WAECHTER ETAL CONTROL MECHANISM FOR CRAWLER LOADER BOOMS Filed Jan. 25, 1928 2 Sheets-Sheet 1 zzz/erzzans. lowlfin yder (Zia/224%! Aug. 4, 1931. F. F. WAECHTER ETAL 1,317,739 CONTROL MECHANISM FOR CRAWLER LOADER BOOMS Filed Jan. 25, 1928 2 Sheets-Sheet 2 Patented Aug. 4, 1931 UNITED STATES PATENT OFFICE FERDINAND F. WAECHTER- ANDLOUIS F. SNYDER; OF PHILADELPHIA, PENNSYL- VANIA, ASSIGNORS TO LINK-BELT COMPANY, OF CHICAGO, ILLINOIS, A CORPORA TION OF ILLINOIS CONTROL MECHANISM FOR CRAWLER LOADER BOOMS Application filed January 25, 1928. Serial No. 249,231;

Our invention relates to improvements in excavating machines and has for one object to provide a control mechanism for a crawler loader boom. Another object of the invention is to provide a control mechanism for that type of crawler loader boom wherein the boom is overweighted at the rear end tending normally to rotate by gravity away from the'work and our purpose is to provide means whereby the boom may be longitudinally displaced toward and from the work and at the same time by manipulation of the same displacing means may be rotated from the idle into the Working position. Other objects of the invention will appear from time to time in the specification and claims.

The invention is illustrated more or less.

diagrammatically in the accompanying drawings wherein we have shown only the essential parts of the mechanism; that is, the parts having to do with our present invention and it will be understood that the details of the crawler loader, the boom; the supporting mechanism and'the like are adequately illustrated in ourco-pending application Serial Number 24-1 756, filed Decem ber 22, 1927. Figure 1 is a side elevation; Figure 2 is anenlarged section taken on line 22 of Figure 1; and Figure is a front elevation. Like parts are indicated by like characters throughout the specification and drawings. V A is a supporting frame which may, be mounted on any'suita'ble truck, carriage or tractor and may be movedby hand or power as desired. A A are downwardly inclined supporting tracks on the front end of the frame A, along which travel flanged rollers A rotatable on the boom axle A A is an excavator boom-pivoted on the axle A It will be understood that this boom is adapted to carry the usual type of conveying mechanism such as a belt or chain with buckets and the like and that it'is intended to have at the lower end an excavating or digging mechanism of any suitable type which may be operated separatelyfrom or in unisonwith travel along the tracks A to be held in position thereon 'by the cover plates A B B are sheaves mounted rigidly on the outer ends of the axle A B B are guide and tilting pulleys mounted on the boom A. B is a hoisting and tilting cable dead ended onthe axle of the sheave B at the upper end of each of the tracks A This cable extends down by a pulley B thence up over a sheave B thence down about the tilting pulley B and thence down to a drum B, there being two of these drums mounted on a single drum shaft B which shaft carries a gear B in. mesh with a pinion B which in turn rotates with a gear B in mesh with a pinion B adapted to be rotated by a hand wheel B or if preferred by any suitable power means or motor not here shown. Suitable means are provided applied'to a drum shaft B in the form of a brake drum B brake band B controlled by alever B 'to lock the drums B in any suitable position to adjust" the-"boom along the tracks A v G C are a pair of limit chains interposed between the upper ends of the tracks and the axle A and adapted to preventmovement of the rollers A and the boom down off the track. 7

It will be understood that the center of gravity of the boom is at a point behind and above the axis of rotation or the supporting line where it'is supported onthe track by means of the axle so that the boom tends to tilt in a counter clockwise direction toward the horizontal, the boom wheirin such position raising at its rear end on the frame. This tilting tendency is normally resisted by the cover plates A engaging the upper sides of the rollers A and constrainingthe boom to 'a rectilinear movement generally along its axis. in a direction parallel to its tracks A A and as long as the boom is in the working position and held against rotation manipulation of the drive wheel B drawing or paying out on the cable B serves merely to move the boom back and forth in a direction parallel to the tracks limited at its upper end by engagement with the sheaves B B and at its lower end by the limit chains.

hen it is desired to collapse the boom the operator will lower the boom either until the limit chain supports the load or until the end of the boom rests on the ground. He will then remove the cover plates A which may be held in place by any suitable means such as bolts, lugs or the like and thus leave the rollers A free to rotate with the boom away from the track A If the downward thrust component of the boom along the track is supported by the limit chains and it the cable B is tight, the cable extending from the sheave B from the drum B will resist its rotation and the operator will then pay out on the cable.

' Since the limit chains permit no further movement of the sheave 13 away from the sheave B, this paying out of the cable will permit the boom to rotate toward a horizontal position of rest. If on the other hand the boom is resting on the ground and the chains are not carrying the load as soon as the operator pays out on the cable B the boom will tend to rotate and will at the same time tend to travel down along the track and it will continue this downward travel along the track until the limit chains have been brought into tension at which time further movement along the track will cease and the boom will be limited to a rotary movement.

When the operator wishes to return the boom to the working position he will merely pull down on the cable tilting the boom until the auxiliary rollers A are brought into engagement with the tracks, the cover plate will be replaced and then by manipulation of the cable the boom can be operated toward and from the work in the usual manner.

To claim:

1. In a material handling device, an in clined track, a boom pivotally and longitudinally movable therealong, means for moving the boom upwardly along a track and for angularly displacing it, said means being operative to angularly displace the boom only when it is in its extreme clownward position.

2. In a material handling device, an inclined track, a boom, pivotally and longitudinally movable therealong, means for limiting its downward movement therealong, means for moving the boom upwardly along the track and when the boom. is in its egrtreme downward position only for angularly displacing it, the center of gravity of the boom being located above its pivot point.

3. In a material handling device, an inclined track, a boom, pivotally and longitudinally movable therealong, means for limiting its downward movement therealong, means for moving the boom upwardly along the track and when the boom is in its extreme downward position only for angularly displacing it, the boom raising and pivot controlling means comprising a cable, sheaves on boom and track over which the cable travels and a separate sheave on the boom at a point removed from its pivot point over which the cable travels.

4. In a material handling device, an inclined track, a boom, pivotally and longitudinally movable therealong means for limiting its downward movement there along, means for moving the boom upwardly along the track and when the boom is in its extreme downward position only for angularly displacing it, the center of gravity of the boom being located above its pivot point, the boom raising and pivot controlling means comprising a cable, sheaves on boom and track over which the cable travels and a separate sheave on the boom at a point removedfrom its pivot point over which the cable travels.

5. In a material handling device, an inclined track, a boom pivotally and longitudinally movable therealong, a limit chain interposed between the boom and the track to positively limit its downward movementalong the track, a sheave associated with the track, a sheave located at the center of rotation of the boom, a sheave located on the boom at a point removed from its center, a cable passing about all said sheaves, means removed from the track for hauling in on the free ends of the cable whereby when the boom is supported by the limit chain the cable may be manipulated to control the rotation of the boom.

6. In a material handling device, an inclined track, a boom pivotally and longitudinally movable therealong, a limit chain interposed between the boom and the track to positively limit its downward movement along the track, a sheave associated with the track, a sheave located at the center of rotation of the boom, a sheave located on the boom at a point removed from its center, a cable passing about all said sheaves, means removed from the track for hauling in on the free-ends of the cable whereby when the boom is supported by the limit chain the cable may be manipulated to control the rotation of the boom, the center of gravity of the boom being on the side of the pivot thereof opposed to the last mentioned sheave.-

7- A loader compri ng a support, a downwardly and forwardlyinclined track thereon, a boom, rollers interposed between the boom and the track, excavating and loading machinery carried by the boom, the center of gravity of the boom being so positioned with respect to the supporting rollers that it tends to rotate out of the working toward a general horizontal position, a cable associated with the support and the boom and adapted to move the boom upwardly along the track and a limit chain interposed be-- tween the boom and the track for limiting the downward movement of the boom.

8. A loader comprising a support, a downwardly and forwardly inclined track thereon, a boom, rollers interposed between the boom and the track, excavating and loading machinery carried by the boom, the center of gravity of the boom being so positioned with respect to the supporting rollers that it tends to rotate out of the working toward a general horizontal position, a cable associated with the support and the boom and adapted to move the boom up- Wardly along the track and a limit chain interposed between the boom and the track for limiting the downward movement of the boom, means interposed between the cable and the boom whereby the tension on the cable when the boom is supported by the limit chain may be used to rotate the boom downwardly toward the working position.

9. A loader comprising a supporting frame, an inclined track thereon, a sheave at the upper end thereof, a boom, a roller interposed between it and the track, a sheave concentric with the roller on the boom, a sheave at a point removed from the center of rotation of the boom, a hoisting mechanism on the support, a cable traveling about said sheaves and terminating at the hoisting mechanism, a limit chain interposed between the boom and track to positively limit the downward movement of the boom therealong.

10. A loader comprising a supporting frame,-an inclined track thereon, a sheave at the upper end thereof, a boom, a roller interposed between it and the track, a sheave concentric with the roller on the boom, a sheave at a point removed from the center of rotation of the boom, a hoisting mechanism on the support, a cable traveling about said sheaves and terminating at the hoisting mechanism, a limit chain interposed between the boom and track to positively limit the downward movement of the boom therealong, an auxiliary track on the support and a roller on the boom adapted to be brought into engagement with said track, means associated with said last track for constraining the roller to a path parallel therewith.

11. A loader comprising a supportlng frame, an inclined track thereon, a sheave at theupper end thereof, a boom, a roller interposed between it and the track, a sheave concentric with the roller on the boom, a sheave at a point removed from the center of rotation of the boom, ahoisting mechanism on the support, a cable traveling about saidsheaves and terminating at the hoisting mechanism, a limit chain interposed between the boom and track to positively limit the downward movement of the boom therealong, an auxiliary track on the support and a roller on the boom adapted to be brought into engagement with said-track means associated with said last track for constraining the roller to a path parallel therewith, said means being releasable.

12. In a material handling device, an inclined track, a boom pivotally and longitudinally movable therealong, means independent of the track for limiting its downward movement therealong, means for moving the boom upwardly along the track and for rotating the boom about its pivot point the boom when rotating being supported only at its central portion,

13. In a material handling device, an in-,

clined track, a boom pivotally and longitudinally movable therealong, means inde-' pendent of the track for limiting its downward movement therealong, means for moving the boom upwardly along the track and for rotating the boom about its pivot point, said rotating means being effective only when the boom is at its extreme lower posltion. I I

14. In a material handling device, a track, a boom pivotally and longitudinally movable therealong, means independent of the track for limiting", the movement of the boom therealong and means for rotating the boom about its pivot on the track the boom whenv rotatingbeing supported only at its] central portion. 15. In amaterial. handling device, a track, a boom plvotally and longitudinally movable therealong, means independentof'the' track for limiting the movement of the boom therealong and means for'rotating the boom about its pivoton the track, said means being. effective only when the boom is atone end of its excursion along the track; 16. In a material handling device, an inclined track, a boo'mpivotally and longitu-.

dinally movable therealong, means interposed between theboom and the track to positively limit its downward movement along the track, a sheave associated with the track, a sheave located at the center of rotation of the boom," a sheave located on the boom at a point removed from its cen ter, a cable passing about all said sheaves, means removed from the track for hauling in on the free endsof the cable whereby when theboom is supported by the limit chain the cable may be manipulated to control the rotation of the boom.

17 In a material handling device, an inclined track, a boom pivotally and longitudinally movable therealong, means interposed between the boom and the track to positively limit its downward movement along the track, a sheave associated with the track, a sheave located at the center of rotation of the boom, a sheave located on the boom at a point removed from its center, a cable passing about all said sheaves, means removed from the track for hauling in on the free ends of the cable whereby when the boom is supported by the limit chain the cable may be manipulated to control the rotation of the boom, the center of gravity of the boom being on the side of the pivot thereof opposed to the last mentioned sheave.

18. A loader comprising a support, a downwardly and forwardly inclined track thereon, a boom, rollers interposed between the boom and the track, excavating and loading machinery carried by the boom, the center of gravity of the boom being so positioned with respect to the supporting rollers that it tends to rotate out of the working toward a general horizontal position, a cable associated with the support and the boom and adapted to move the boom upwardly along the track and means interposed between the boom and the track for limiting the downward movement of the boom.

19. A loader comprising a support, a downwardly and forwardly inclined track thereon, a boom, rollers interposed between the boom and the track, excavating and loading machinery carried by the boom, the center of gravity of the boom being so positioned with respect to the supporting rollers that it tends to rotate out of the work ing toward a general horizontal position, a cable associated with the support and the boom and adapted to move the boom upwardly along the track and means interposed between the boom and the track for limit-ing the downward movement of the boom, means interposed between the cable and the boom whereby the tension on the cable when the boom is supported by the limit means may be used to rotate the boom downwardly toward the working position.

20. A loader comprising a supporting frame, an inclined track thereon, a sheave at the upper end thereof, a boom, a roller interposed between it and the track, a sheave concentric With the roller on the boom, a sheave at a point removed from the center of rotation of the boom, a hoisting .mechanism on the support, a cable traveling about said sheaves and terminating at the hoisting mechanism, means in.ter-.

posed between the boom and track to positively limit the downward movement of the boom therealong.

21. A loader comprising a supporting frame, an inclined track thereon, a sheave at the upper end thereof, a boom, a roller interposed between it and the track, a sheave concentric with the roller on the boom, a sheave at a point removed from the center of rotation of the boom, a hoisting mechanism on the support, a cable traveling about said sheaves and terminating at the hoisting mechanism, means interposed between the boom and track to positively limit the downward movement of the boom therealong, an auxiliary track on the support and a roller on the boom adapted to be brought into engagement with said track, means associated with said last track for constraining the roller to a path parallel therewith.

22. A loader comprising a supporting frame, an inclined track thereon, a sheave at the upper end thereof, a boom,a roller in terposed between it and the track, a sheave concentric with the roller on the boom, a sheave at a point removed from the center of rotation of the boom, a hoisting mechanism on the support, a cable traveling about said sheaves and terminating at the hoisting mechanism, means interposed between the boom and track to positively limit the downward movement of the boom therealong, an auxiliary track on the support and a roller on the boom adapted to be brought into engagement with said track means associated with said last track for constraining the roller to a path parallel therewith, said means being releasable.

Signed at Philadelphia, county of Philadelphia and State of Pennsylvania, this 17th day of January, 1928. I

FERDINAND F. XVAECHTER.

LOUIS F. SNYDER. 

